1. Field of the Invention
The present invention relates to a developer container used in an image forming apparatus such as a copying machine, a printer or a facsimile machine, a method of manufacturing a process cartridge, a developer container and a process cartridge.
2. Description of the Related Background Art
Conventionally, in an image forming apparatus (developing device) such as an electrostatic copying machine or a printer, powder toner is used in conducting image formation (development). A developer container that contains toner therein for supplying the toner when the toner is consumed in a developing device is made up of a cylindrical or rectangular parallelepiped container main body which is made of synthetic resin, and a sealing member that seals a toner discharge opening for discharging the toner from the container main body to the image forming apparatus (developing device) to supply the toner to the image forming apparatus.
The sealing member is so disposed as to prevent the toner from being leaked from the toner discharge opening even if some vibrations occur or the developer container is accidentally caused to drop down during a process of conveying the developer container to a store or a user from a manufacturing factory (in the distribution process). Therefore, the sealing member is appropriately welded to the container main body so that the toner does not leak from the toner discharge opening.
Also, in an electrophotographic image forming apparatus using an electrophotographic image forming process, there is applied a process-cartridge system in which an electrophotographic photosensitive member and a process means effected on the electrophotographic photosensitive member are integrated into a cartridge, and cartridge is detachably mountable on an electrophotographic image forming apparatus main body.
According to the process-cartridge system, since the maintenance of the image forming apparatus can be conducted by a user per se not relying on a service person, the operationality can be remarkably improved. For that reason, the above process-cartridge system is widely employed in the electrophotographic image forming apparatus.
The process cartridge thus structured includes a developing chamber in which a developing roller is disposed as a developing means, and a containing chamber that contains the developer therein, and a toner discharge (supply) opening, which is disposed in the containing chamber and communicates with the developing chamber, is sealed with the sealing member during the manufacture of the process cartridge. Then, the user removes the sealing member from the containing chamber before starting the use of the process cartridge, to thereby supply the toner to the developing chamber from the containing chamber. This structure prevents the toner from being leaked from the containing chamber before the process cartridge is used.
The sealing members are of an easy peeling type in which the toner discharge opening is sealed with one sheet and a welding portion of the film is peeled from the container main body to unseal the opening, and of a tearing type in which a pat of the film is torn up so that the welding portion of the film remains in the container main body, to thereby unseal the opening.
As the type in which the film is torn up, there have been proposed a tear tape system in which a cover film and a tear tape are integrated together, and at the time of starting to use the process cartridge, the tear tape is pulled so that the cover film is torn up by the tear tape to unseal the toner discharge opening, and a system in which one tearing sealing member is employed. Those methods are frequently employed these days because they are advantageous in that the unsealing strength can be lessened and the opening width can be controlled. A method using the one tear sealing member has been proposed in Japanese Patent Application Laid-Open No. 59-13262, Japanese Utility Model Application Laid-Open No. 63-60164, and the like.
Also, as a method of fixing the sealing member to the developer container main body, there are generally provided a melting method using a heat seal, an impulse seal, a high-frequency welding, an ultrasonic welding and so on, and a bonding method using an adhesive double coated tape, a bonding tape and so on. In particular, one means employing a fixing method using the impulse seal is disclosed in Japanese Patent Application Laid-Open No. 5-6091, Japanese Patent Application Laid-Open No. 8-160727 and the like.
However, since the above systems of tearing up the film are so structured as to tear up the sealing member due to a user""s force, it is preferable to structure the system so that the sealing member is torn up by a force as small as possible. However, in the conventional system of tearing the film, there is a possibility that the sealing member is unintentionally torn up to unseal the toner discharge opening during the above-mentioned circulation.
The present invention has been made under the above circumstances, and therefore an object of the present invention is to provide a method of manufacturing a developer container which is capable of excellently sealing the opening of the developer container with a sealing member.
Another object of the present invention is to provide a developer container in which the opening of the developer container is excellently sealed with a sealing member.
Still another object of the present invention is to provide a method of manufacturing a process cartridge which is capable of excellently sealing the opening of the developer container with a sealing member.
Yet still another object of the present invention is to provide a process cartridge in which the opening of the developer container is excellently sealed with a sealing member.
Yet still another object of the present invention is to provide a method of manufacturing a developer container which is capable of excellently removing the sealing member that seals the opening of the developer container.
Yet still another object of the present invention is to provide a developer container which is capable of excellently removing the sealing member that seals the opening of the developer container.
Yet still another object of the present invention is to provide a method of manufacturing a process cartridge which is capable of excellently removing the sealing member that seals the opening of the developer container.
Yet still another object of the present invention is to provide a process cartridge which is capable of excellently removing the sealing member that seals the opening of the developer container.